The FMI 3.0-beta.3 pre-release is available on github.com/modelica/fmi-standard/releases.

This Beta.3 will very likely be release candidate RC.1 (unless major flaws in API or XSD are uncovered). This means the C-API and the XSD files can be considered stable from now on.

The changes compared to 3.0-beta.2 are listed here